Hi Maria, I would say: d) wait it's an Object method and releases the lock on the particular object whose reference was used to call it. e) stop it's a Thread method and releases all the locks one Thread has. ------------ a) yield keeps the locks and only allows Threads that are in a runnable state (not waiting on a lock for instance) to run. b) sleep keeps the lock and temporarily cease execution for the specified time c) interrupt is called from another Thread on a Thread that is waiting, sleeping, or blocked in a I/O d) suspend holds its threads.